Wordia - The Definition Of Permutation
permutation
noun, maths a) an ordered arrangement of the numbers, terms, etc, of a set into specified groups b) a group formed in this way. The number of permutations of n objects taken r at a time is n!/(n–r)!. Symbol: nPr ▷ See also combination
From Collins
©HarperCollins 2008. Collins English Dictionary definition of permutation